Exhibit 5.1


                             W.S. WALKER & COMPANY
                               Attorneys-at-Law
                        Caledonian House, P.O. Box 265
                           George Town, Grand Cayman
                                Cayman Islands
                   Tel: (345) 949-0100  Fax: (345) 949-7886
                           Internet: walker@candw.ky

                                                  Our Ref:  GC/MPL/fm/A181-09400

29th March, 1999


Apex Silver Mines Limited
Caledonian House
Jennett Street
P.O. Box 1043
George Town
Grand Cayman
CAYMAN ISLANDS

Dear Sirs:

This opinion is delivered in connection with the filing of a Registration
Statement on Form S-3 (the "Registration Statement") filed with the Securities
Exchange Commission under the U.S. Securities Act of 1933, as amended (the
"Act"), by Apex Silver Mines Limited, a Cayman Islands company ("Apex"), for the
registration of the sale from time to time of up to US$200,000,000 aggregate
amount of (i) ordinary shares, par value US$0.01 per share, of Apex ("Ordinary
Shares"), (ii) depositary shares of Apex ("Depositary Shares"), (iii) preference
shares, par value US$0.01 per share of Apex ("Preference Shares"), (iv) warrants
for the purchase of preference shares or ordinary shares of Apex ("Warrants"),
(v) rights to purchase ordinary shares of Apex ("Ordinary Share Purchase
Rights") and (vi) senior debt securities and/or subordinated debt securities of
Apex ("Debt Securities") (each of the Ordinary Shares, the Depositary
Shares, the Preference Shares, the Warrants, the Ordinary Share Purchase Rights
and the Debt Securities referred to herein as a "Security" and collectively
referred to herein as, the "Securities").

For the purposes of giving this opinion, we have examined the documents (the
"Documents") listed in Schedule 1 hereto.

In giving this opinion we have relied upon the assumptions set out in Schedule 2
hereto, which we have not independently verified.

We are Attorneys-at-Law in the Cayman Islands and express no opinion as to any
laws other than the laws of the Cayman Islands in force and as interpreted at
the date hereof.  Except as explicitly stated herein, we express no opinion in
relation to any representation or warranty contained in the documents nor upon
the commercial terms of the transactions contemplated by the documents.

Based upon the foregoing examinations and assumptions and upon such searches as
we have conducted and having regard to legal considerations which we deem
relevant, we are of the opinion that under the law of the Cayman Islands:

 
1.   With respect to each of the Ordinary Shares, when (i) the Board of
     Directors of Apex or a committee thereof properly empowered (such Board of
     Directors or committee being hereinafter referred to as the "Apex Board")
     has taken all necessary corporate action to approve the issuance of and the
     terms of the offering of the Ordinary Shares and related matters, and (ii)
     entries have been made in the Register of Members of Apex and certificates
     representing the Ordinary Shares have been duly executed, countersigned,
     registered and delivered (a) for consideration approved by the Apex Board
     or (b) upon consideration by way of conversion or exercise of any other
     Security in accordance with the terms of such Security or the instrument
     governing such Security providing for such conversion or exercise as
     approved by the Apex Board, the Ordinary Shares will be duly authorized,
     validly issued, fully paid and non-assessable.

2.   With respect to the Preference Shares, when (i) the Apex Board has taken
     all necessary corporate action to approve the issuance and terms of the
     Preference Shares, the terms of the offering thereof and related matters,
     including the adoption of resolutions establishing the terms of such
     Preference Shares, and (ii) entries have been made in the Register of
     Members of Apex and certificates representing the Preference Shares have
     been executed, countersigned, registered and delivered (a) for
     consideration approved by the Apex Board or (b) upon consideration by way
     of conversion or exercise of any other Security in accordance with the
     terms of such Security or the instrument governing such Security providing
     for such conversion or exercise as approved by the Apex Board, the
     Preference Shares will be duly authorized, validly issued, fully paid and
     non-assessable.

3.   With respect to the Depositary Shares, when (i) the Apex Board has taken
     all necessary corporate action to approve the issuance and terms of the
     Depositary Shares, the terms of the offering thereof and related matters,
     including the adoption of resolutions establishing the terms of such
     Depositary Shares, and (ii) entries have been made in the Register of
     Members of Apex and certificates representing the Depositary Shares have
     been executed, countersigned, registered and delivered (a) for
     consideration approved by the Apex Board or (b) upon consideration by way
     of conversion or exercise of any other Security in accordance with the
     terms of such Security or the instrument governing such Security providing
     for such conversion or exercise as approved by the Apex Board, the
     Depositary Shares will be duly authorized, validly issued, fully paid and
     non-assessable.

4.   With respect to the Ordinary Share Purchase Rights, when (i) the Apex Board
     has taken all necessary corporate action to approve the issuance and terms
     of the Ordinary Share Purchase Rights, the terms of the offering thereof
     and related matters, including the adoption of resolutions establishing the
     terms of such Ordinary Share Purchase Rights, and (ii) certificates
     representing the Ordinary Share Purchase Rights have been executed,
     countersigned, registered and delivered for consideration approved by the
     Apex Board, the Ordinary Share Purchase Rights will be duly authorized and
     validly issued.

5.   With respect to the Warrants, when (i) the Apex Board has taken all
     necessary corporate action to approve and enter into one or more relevant
     warrant agreements or amendments or supplements thereto, as described in
     the Registration Statement, as amended or supplemented, or any prospectus
     or prospectus supplement and pursuant thereto, approve the issuance and
     terms of the Warrants, the terms of the offering thereof and related
     matters, including the adoption of resolutions establishing the terms of
     such Warrants, and (ii) certificates representing the 

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     Warrants have been executed, countersigned, registered and delivered for
     consideration approved by the Apex Board, the Warrants will be duly
     authorized and validly issued.

6.   With respect to the Debt Securities, when (i) the Apex Board has taken all
     necessary corporate action to approve and enter into one or more relevant
     indentures or amendments or supplements thereto, as described in the
     Registration Statement, as amended or supplemented, or any prospectus or
     prospectus supplement and pursuant thereto, approve the issuance and terms
     of the Debt Securities, the terms of the offering thereof and related
     matters, including the adoption of resolutions establishing the terms of
     such Debt Securities, and (ii) certificates representing the Debt
     Securities have been executed, countersigned, registered and delivered for
     consideration approved by the Apex Board, the Debt Securities will be duly
     authorized and validly issued.

This opinion is limited to the matters referred to herein and shall not be
construed as extending to any other matter or document not referred to herein.
This opinion is given solely for your benefit and the benefit of your legal
advisers acting in that capacity in relation to this transaction and may not be
relied upon by any other person without our prior written consent.  This opinion
is governed by and shall be construed in accordance with the laws of the Cayman
Islands.

We hereby consent to the filing of this opinion as an Exhibit to the
Registration Statement and all references to our name in the Registration
Statement.  In giving such consent, we do not hereby admit that we come within
the category of persons whose consent is required under Section 7 of the U.S.
Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission thereof.


                                Yours faithfully,

 
                                /s/ W.S. Walker & Company
                                W.S. Walker & Company

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                                  Schedule 1
                                        

1.  The Memorandum and Articles of Association of Apex;

2.  The Registration Statement; and

3.  Such other documents as we have considered necessary for the purposes of
    rendering this opinion.

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                                  Schedule 2
                                        

The opinions hereinbefore given are based upon the following assumptions:

1.  There are no provisions of the laws of any jurisdiction outside the Cayman
    Islands which would be contravened by the execution or delivery of the
    Documents and that, in so far as any obligation expressed to be incurred
    under the Documents is to be performed in or is otherwise subject to the
    laws of any jurisdiction outside the Cayman Islands, its performance will
    not be illegal by virtue of the laws of that jurisdiction.

2.  All authorizations, approvals, consents, licenses and exemptions required by
    and all filings and other requirements of each of the parties to the
    Documents outside the Cayman Islands to ensure the legality and validity of
    the Documents will be duly obtained, made or fulfilled and will remain in
    full force and effect and that any conditions to which they are subject will
    be satisfied.

3.  None of the parties to any of the Documents will be

    (a)  a "person in Iraq" as that term is defined in The Iraq and Kuwait
         (United Nations Sanctions) (Dependent Territories) Order 1990 or an
         "Iraqi person" as defined in The Iraq (United Nations) (Sequestration
         of Assets) (Dependent Territories) Order 1993 or a person resident in
         the Republic of Iraq for the purposes of the Caribbean Territories
         (Control of Gold, Securities, Payment and Credits:  Kuwait and
         Republic of Iraq) Order 1990; or

    (b)  a "person connected with Libya" as that term is defined in The Libya
         (United Nations Sanctions) (Dependent Territories) Order 1992.

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